Android phone only detects certain sim cards?

Can anyone explain to me why my cell phones only detect and show that a sim is inserted for certain sim cards? For example, my S3 is able to detect a Koodo micro sim, but when I put in a Fido micro sim, it will not detect it and say no sim card inserted. Same goes for my spare dual sim phone. Any reasons why?

Can anyone explain to me why my cell phones only detect and show that a sim is inserted for certain sim cards? For example, my S3 is able to detect a Koodo micro sim, but when I put in a Fido micro sim, it will not detect it and say no sim card inserted. Same goes for my spare dual sim phone. Any reasons why?

This could happen because your phone might be locked to a particular carrier. Search your device forum for help on unlocking.

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